Matter is conserved


Energy flows, but matter is recycled


Importance of biogeochemical cycling


Cycling = Transfer, transformation and storage


Biogeochemical cycles: Global


Nutrient cycles: Ecosystem




  • Entry of nutrients into system (IN)
    • fixation (bacteria)
    • weathering (rocks)
    • deposition (acid rain)


  • Internal transfer (recycling)
    • food webs
    • decomposition


  • Loss of nutrients from system (OUT)


  • Steady State = ?

Carbon cycle: Ecosystems


Carbon cycle: Global


Nitrogen cycle: Ecosystems


Nitrogen cycle: Ecosystems


Decomposition


Decomposition rate: Biomes



Nutrient transfer: Soil commmunity


Nitrogen cycle: Global


Primary productivity: Generation of biomass


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